Automated near Field Spatial Mapping for Multilayer Ground Split Noise Detection
Automated near field spatial mapping identifies hidden split-plane return current loops and isolates board-level electromagnetic noise sources before EMI certification.
Radiated Emission Mitigation
Energy Suppression
Inside the design cycle for electromagnetic compliance, applying specific modifications to a circuit assembly reduces the intensity of waves exiting the system. Engineering teams apply radiated emission mitigation through a combination of board layout, layer stackup, component selection and mechanical shielding. The methodology targets the sources of radiation to prevent interference with other electronic devices.
Shielding Application
Metal cans or conductive gaskets are used to block radiation from high speed processors or switching power supplies. During the process of radiated emission mitigation, these shields are grounded to the reference plane to provide a low impedance path for noise. This physical barrier prevents both the emission of interference and the reception of external noise.
Shielding is often used as a final measure when board level changes are not sufficient. Metallic enclosures or conductive coatings are applied to the interior of plastic housings to further contain the electromagnetic energy. Grounding the shield at multiple points ensures that it does not become a resonant structure at higher frequencies.
Component Filtering
Choosing components with low parasitic inductance also helps in maintaining signal purity and reducing emissions. Ferrite beads and common mode chokes are placed on cables and connectors to prevent them from acting as antennas. This aspect of the mitigation strategy targets the conducted energy that would otherwise radiate from external wiring.